By CHATOOWA NDHLOVU
Cholera is an infectious disease that causes severe watery diarrhea, which can lead to dehydration and even death if untreated.
It is caused by eating food or drinking water contaminated with a bacterium called Vibrio Cholerae.
The disease is most common in places with poor sanitation, crowding, war, and famine.
Causes of Cholera
Vibrio Cholerae, the bacterium that causes cholera, is usually found in food or water contaminated by feces.
Common sources include: foods and drinks sold on the streets by street vendors, vegetables grown in water containing human wastes, uncooked fish caught from water sources containing human waste, etc.
When an individual ingests contaminated food or water having the Vibrio Cholerae, the bacterium produces cholera toxin that cause cells lining the intestines to release increased amounts of water, leading to diarrhea and rapid loss of fluids and electrolytes (salts).
Symptoms of cholera can begin as soon as a few hours or as long as five days after infection. Often, symptoms are mild.
But sometimes they are very serious.
About one in 20 people infected have severe watery diarrhea accompanied by vomiting, which can quickly lead to dehydration.
Signs and symptoms of dehydration include: rapid heart rate, thirst, muscle cramps, loss of skin elasticity (the ability to return to original position quickly if pinched), dry mucous membranes – including the inside of the mouth, throat, nose, and eyelids, low blood pressure, if not treated, dehydration can lead to shock and death in a matter of hours.
The history of cholera
The first cholera pandemic emerged out of the Ganges Delta with an outbreak in Jessore, India, in 1817, stemming from contaminated rice.
The disease quickly spread throughout most of India, modern-day Myanmar, and modern-day Sri Lanka by travelers along trade routes established by Europeans.
By 1820, cholera had spread to Thailand, Indonesia (killing 100,000 people on the island of Java alone) and the Philippines.
From Thailand and Indonesia, the disease made its way to China in 1820 and Japan in 1822 by way of infected people on ships.It also spread beyond Asia.
In 1821, British troops traveling from India to Oman brought cholera to the Persian Gulf.
The disease eventually made its way to European territory, reaching modern-day Turkey, Syria and Southern Russia.
The second cholera pandemic began around 1829.
Like the one that came before it, the second pandemic is thought to have originated in India and spread along trade and military routes to eastern and central Asia and the Middle East.
By autumn of 1830, cholera had made it to Moscow.
The spread of the disease temporarily slowed during the winter, but picked up again in spring of 1831, reaching Finland and Poland.
It then passed into Hungary and Germany.
The disease subsequently spread throughout Europe, including reaching Great Britain for the first time via the port of Sunderland in late 1831 and London in spring of 1832.
Britain enacted several actions to help curb the spread of the disease, including implementing quarantines and establishing local boards of health.
In 1832, cholera had also made it to the Americas.
In June of that year, Quebec saw 1,000 deaths from the disease, which quickly spread along the St. Lawrence River and its tributaries.
Around the same time, cholera imported into the United States (US), appearing in New York and Philadelphia.
Over the next couple of years, it would spread across the country.
It reached Latin America, including Mexico and Cuba, in 1833.
It was in the year 1850 that Zachary Taylor, the 12th president of the United States, died suddenly from an attack of Choleramorbus.
He was succeeded by Millard Fillmore.
The third pandemic, stretching 1852–1859, was the deadliest. It devastated Asia, Europe, North America and Africa, killing 23,000 people in Great Britain alone in 1854, the worst single year of cholera.
It was till this period that scientists developed the urge to study how this deadly disease was being transmitted, British biologist John Snow, who’s considered one of the fathers of modern epidemiology, carefully mapped cholera cases in the Soho area of London.
This allowed him to identify the source of the disease in the area which had contaminated water from a public well pump.
He convinced officials to remove the pump handle, immediately dropping the cholera cases in the area, later he published his discovery on the mode of transmission of the disease through contaminated water and food.
In 1883, German microbiologist Robert Koch, the founder of modern bacteriology, studied cholera in Egypt and Calcutta.
He developed a technique allowing him to grow and describe Vibrio Cholerae, and then show that the presence of the bacterium in intestines causes cholera.
However, Italian microbiologist Filippo Pacini had actually identified the cholera bacterium naming it Cholerigenicvibrios—in 1854 where the current name of the bacterium Vibrio Cholerae is derived.
Cholera outbreak in Zambia
The cholera outbreak initially started in the Chipata sub-district and spread to Kanyama sub-district around October 9, 2017.
The outbreak has spread from the peri-urban townships on the western part of Lusaka to the eastern part with a new case reported in Chelstone sub-district.
As of December 7, 2017 the affected sub-districts include Chipata, Kanyama, Chawama, Matero, Chilenje and Chelston.
George compound has been named the latest cholera epic sub-district.
These compounds which are densely populated and have an inadequate water and sanitation infrastructure, had favored the spread of the disease.
The sources of infection transmission in the outbreak has been associated with contaminated water supplies, contaminated food, inadequate sanitation and poor hygiene practices.
In the recent developments we have been recording decreasing numbers of cholera incoming cases because of the huge step the Government has taken in making sure that the streets of Lusaka and shanty compounds are cleaned and that good sanitary practices are observed in the capital city, these works have helped to curb the spread of the disease.
Treatment of cholera
Cholera does not require highly technical treatment, and up to 80 per cent of victims survive if treated with rehydration.
An epidemic can be stopped by rehydration of victims and establishing basic sanitation. Rehydration may be accomplished using simple oral rehydration fluid.
This may be a product similar to commercial pediatric electrolyte solutions, but an effective oral replacement can be as simple and inexpensive as a solution of clean water with a small amount of sugar and salt.
More severe cases of dehydration when a person cannot drink even small sips require IV fluids.
Antibiotic treatment of infected individuals is also used to shorten the course of illness and the duration of shedding of the bacteria in stool.
Effective antibiotics against cholera include tetracycline, doxycycline (Vibramycin), sulfa drugs such as trimethoprim (Primsol) and trimethoprim/sulfamethoxazole (Bactrim), ciprofloxacin (Cipro), erythromycin (Ery-Tab), and azithromycin (Zithromax).
Education and awareness campaigns in epidemic areas permit early treatment of those infected, as well as establishing local prevention measures.
Vaccination is an important tool in outbreak control.
The World Health Organization (WHO) stocks two oral cholera vaccines (Dukoral and Shanchol) that have been used successfully in mass vaccination campaigns, like the case currently in Zambia.
The author is a first year student at the University of Zambia in the School of Natural Sciences. Cell No. 0972886711, 0966431441. Email Address: firstname.lastname@example.org.